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Coupler-Decoupler Network Product Family

This family is available in two versions:

S46xxx are ‘standard’ CDNs with the versatile advantages.
E46xxx are ‘Enhanced’ CDNs that have exactly the same versatile advantages as the S series, plus the ability to output a feedback signal corresponding to the level of RF stress applied to the EUT cable.

The network references given below are to EN 61000-4-6:

x46ST6 for shielded and unshielded cables up to six cores.
A general-purpose unit with particular application to power supplies up to 2amps, audio, security system and serial data circuits.
Supplied with three alternative connecting cable sets:  One 50ohm BNC for network S1, one user-configurable as S2- S6 or offering replacements for AF2,  AF3,  AF6,  T2,  T3,  and T6, and one user-configurable as M1- M3,


x46ST8 for shielded and unshielded cables up to eight cores.
Specially suited for high-speed data including “Cat 5” 4-pair cables.
Supplied with three cable sets terminated for STP & UTP 4-pair RJ45 and 2-pair RJ11, allowing configuration as S1-S8 and replacing AFx  & Tx for 1, 2, 4, & 8 cores.


x46S25 for shielded cables up to twenty-five cores.  This can replace any of the Sxx networks and is well-suited to computer modules using D-type or Centronics connectors.  Supplied with D-type and unterminated cable sets.


 x46T24 for unshielded cables,  and multiple twisted pairs of up to twenty-four cores.  This can replace AFxx and Txx networks for 1, 2, 3, 4, 6, 8, 12 and 24 wires and meets most requirements of medium-speed telecommunications and industrial control.  Supplied with two un-terminated sets of cables.


x46M3 for 2 or 3 core mains circuits up to 16amps and for ground connections.  Supplied with two sets of un-terminated cables to cover M1/M2/M3, and a pre-terminated set for IEC/UK13A cables.


46ZZ Impedance Adaptor pair with VCDN interface connectors are for on-site calibration of x46xx VCDN and 22L test adaptor.  Supplied with BNC sockets as standard:  type N to special order. Conforms to the electrical and mechanical requirements of EN 61000-4-6 and has built-in spacing to establish the required 30mm separation from the VCDN.  The two adaptors clip together for safe storage.


46ZC Interface Adaptor between VCDN EUT interface and type N connector. For formal checking of CDN impedance.


46GP An aluminium ground-plane with a sprung retainer to hold one or two CDNs for calibration and use.  Suitable for the formal testing of EUTs up to 190mm x 115mm, and for informal testing of EUTs up to 290mm x 315mm.  Overall dimensions are 515 x 625mm.
An extension plane 46XP of the same overall size is available.  Used together, these allow formal testing of EUTs up to 595 x 225mm,  and informal testing of  EUTs up to 695mm x 425mm,  yet are easy to transport and store when not in use.

Series 46 VCDN Specifications

Injection/receiver circuit:

EUT RF common-mode impedance:

150W +- 20W from 0.15 to 26MHz.
150W + 60 – 45W from 26 to 230MHz.
150W +- 60W from 230 to 300MHz.

For E46xx the whole of this impedance in provided within the CDN:  For S46xx the CDN provides 100 ohms and relies on the rf source to provide the remainder.

Rf input/output: BNC socket. Maximum continuous input power 3 watts.
For E46xx only: VSWR < 2.5:1 referred to 50W.
Monitor output  (E46xx only): BNC socket. DC to >2KHz. Load > = 1M W
Nominal 1volt dc per volt rms rf carrier or modulation.



User circuit:

As required by EN 61000-4-6 the basic injection impedance of 150W in series with 30nF is applied directly to any cable shield (in the x46S25 and certain configurations of the x46ST6 and x46ST8) and cannot then affect the working circuit.
With unshielded cables proportionately higher-impedance injection components may be connected to each core.  For example, these amount to 450W in series with 10nF from each conductor of a 3-wire mains circuit in x46M3 or a suitably-configured x46ST6, and 3,600W in series with 1.2nF across each of six unshielded balanced pairs configured within an x46T24.
Alternatively, direct connection to the cores of unshielded cables may be avoided by using x46ST6 or x46ST8 or x46S25 in the transformer-coupled configuration of EN55022 figure D3.

Connectors:  Input: 25way D-type male.
Output: 25way D-type female.
Max volts: 250 Vac.
Max. current per core: x46ST6: 1A
x46ST8, x46S25 & x46T24: 0.25A
x46M3: 16A.
Max. unbalanced current per cable: 100mA peak or dc
AE Filter capacitance: x46ST6 nil or 220pF per core with 47nF available on 2 cores;
x46ST8 nil or 47pF per core;
x46S25  none required;
x46T24 47pF per core;  x46M3 47nF on L and N.
All capacitors are safety rated.
Differential-mode characteristic impedance: 50W  for the x46ST6,  x46ST8 and x46S25 in S1 configuration.
Longitudinal conversion loss:  typically >60dB

Dimensions:  115 x 90 x 80mm excluding connectors.

Accessories included:
Comprehensive manual.
Calibration chart (E46xx only).
Input/Output connectors and cables as listed above by product code.